Sectionalized stack

ABSTRACT

A sectionalized stack in which each vertical section has outer and inner upright walls and annular, horizontal flanges connecting the upper and lower ends of the walls to bound an airfilled, insulating chamber is provided with two accordion-like circumferential folds in the inner wall adjacent the respective flanges. The inner wall has a main portion of uniform cross section connecting the folds. The folds being somewhat resilient, the connecting portion can expand vertically and horizontally at a rate different from the rate of expansion of the outer wall when very hot gases rise in the conduit bounded by the inner wall. Distortion of the folds by the weight of the connecting portion is prevented by transferring most of the weight of the connecting portion to the outer wall by means of slidably engaged abutments on the two walls in the insulating chamber.

United States Patent Aug. 14, 1973 Lawrence SECTIONALIZED STACK [76]Inventor: Elllen M. Lawrence, 22 Glenwood Rd., Roslyn, N.Y. 11576 [22]Filed: May 10, 1972 Appl. No.: 252,083

Related U.S. Applicatlon Data Primary Examiner--Kenneth W. SpragueAssistant Examiner-James C. Yeung [5 7] ABSTRACT A sectionalized stackin which each vertical section has outer and inner upright walls andannular, horizontal flanges connecting the upper and lower ends of thewalls to bound an air-filled, insulating chamber is provided with twoaccordion-like circumferential folds in the inner wall adjacent therespective flanges. The inner wall has a main portion of uniform crosssection connecting the folds. The folds being somewhat resil' ient, theconnecting portion can expand vertically'and horizontally at a ratedifferent from the rate of expansion of the outer wall when very hotgases rise in the conduit bounded by the inner wall. Distortion of thefolds by the weight of the connecting portion is prevented bytransferring most of the weight of the connecting portion to the outerwall by means of slidably engaged abutments on the two walls in theinsulating chamber. I

5 Claims, 2 Drawing Figures WIIAVIIJIIIIIIIIII)" y,

PM'ENIH] AUG 1 41975 FIG. 1

SECTIONALIZED STACK CROSS-REFERENCE TO RELATED APPLICATION Thisapplication is a continuation-in-part of the copending application Ser.No. 27,355, filed on Apr. 10, 1970 now U.S. Pat. No. 3,669,042.

BACKGROUND OF THE INVENTION The copending aplication discloses asectionalized smoke stack having an upright, longitudinal axis in whicheach axial section has an outer, tubular, upright wall, an inner,tubular, upright wall, an upper annular flange, and a lower annularflange. The flanges connect the walls, and the flanges and walls jointlybound a chamber normally filled with air which thermally insulates theexposed outer surface of the outer wall from the heat of gases rising inthe conduit bounded by the inner wall.

To compensate for the difference in vertical, thermal expansion betweenthe inner and outer walls, the inner wall is provided with at least oneaccordeon-like, circumferential fold which is somewhat resilient andabsorbs the difference in length changes of the inner and outer walls.When the stack gases are very much hotter than the ambient atmosphere,the difference in radial expansion of the two walls cannot bedisregarded, and it was proposed in the earlier application to providethe flanges with accordeon-like folds extending in a closed loop aboutthe stack axis between the two walls.

SUMMARY OF THE INVENTION It has now been found that differential thermalex-, pansion between the outer and inner walls in a direction transverseto the stack axis can be compensated for adequately, and a stack ofgreater mechanical strength can be obtained without increase in theweight of the same, by providing the inner wall with twocircumferential, accordeon-like folds respectively adjacent the upperand lower flanges, and by directly transmitting at least a portion ofthe weight of the inner wall portion connecting the two folds to theouter wall so as to hold deformation of the resilient folds by theweight of the connecting portion to a minimum.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a fragmentary, elevationalview of a sectionalized stack of the invention; and

FIG. 2 shows a portion of the device of FIG. 1 in elevational section onits upright, longitudinal axis.

DETAILED DESCRIPTION Referring initially to FIG. 1, there are seen threevertically consecutive, identical sections l0, l2, 14 of a stack of theinvention essentially consisting of welded steel plates. The severalsections are connected to each other by axially terminal flanges 16, theupper flange of each section being fixedly fastened to the lower flangeof the next higher section, as by welding.

Each section has a tubular outer wall 18 and a tubular inner wall 20. Asis better seen in FIG. 2, the flanges I6 are annular, horizontal discswhich connect the inner and outer walls 18, 20 so as to define therewitha sealed chamber 22 in each section.

An accordeon-like circumferential fold 24 is formed in the inner wall 20closely adjacent each of the associated flanges l6, and the two folds 24are connected by a portion 26 of the wall 20 which is of uniform crosssection and of an axial length greater than one half of the total axialheight of the section. Each fold 24 constitutes an annular rib 28projecting from the inner wall 20 into the chamber 22, and an annulargroove open toward the central conduit 30 defined by the inner wall andequal in cross section to the opening in each flange 16. The open sideof the groove is covered by a curtain wall 32'fastened to the inner wall20 between the fold and the adjacent flange l6 and freely slidable onthe connecting wall portion 26. The curtain wall 32 prevents theaccumulation in the fold 24 of particulate matter suspended in-the risnggas and minimizes turbulence in the gas that would be caused by anannular gap in the inner wall surface.

As is shown in FIG. 2, the connecting portion 26 of the inner wall 20 isprovided with a fixedly attached, annular disc 34 projectinghorizontally into the chamber 22. It is backed by struts 36 distributedabout the circumference of the disc 34 and extending obliquely from theouter edge of the disc 34 to a part of the connecting wall portion 26above the disc 34. The outer wall 18 is provided with a corresponding,fixedly attached, annular, horizontal disc 38 projecting into thechamber 22 and backed by struts 40 extending from the innercircumference of the disc 38 obliquely downward toward the outer wall 18to which they are fixedly fastened.

The dimensions of the discs 34, 38 are such that the outer rim of thedisc 34 movably abuts from above against the inner rim of the disc 38,thereby transmitting a major portion of the weight of the inner wallportion 26 to the outer wall 18.

When hot gases rise in the central conduit 30 of the illustrated stacksection, the inner wall portion 26 becomes much hotter than the outerwall 18 which is cooled by ambient air. The inner wall portion 26 alsobecomes hotter than the flanges 16 which transmit some of their heat byconduction to the outer wall 1 8. The inner wall portion 26 may expandin an axial and radial direction by causing resilient defonnation of thefolds 24, yet, the folds do not have to support much of the weight ofthe wall portion 26 which is transferred to the outer wall by theabuttingly engaged discs 34, 38.

The discs are normally held in vertical abutting engagement by theweight of the wall portion 26, but are freely movable relative to eachother in a horizontal direction.

Abutments which do not extend about the vertical stack axis in a closedloop may be substitued for the illustrated discs 34, 38, but the latterare preferred where applicable because of the uniform distribution ofthe weight of the wall portion 26 about the circumference of the wall18, and because of the strengthening effect which the discs have on therespective walls 18, 20. The amount of heat transferred by the discs 34,38 from the inner to the outer wall is insignificant because of therelatively small thickness of the discs. Moreover, the flow of heat isimpeded at the abuttingly engaged faces of the discs. If necessary,however, a layer of thermal insulating material may be provided betweenthese faces.

The tubular walls 18, 20 described and illustrated are of circular crosssection, but one or both walls may be of angular cross section, and theflanges and abutment discs modified accordingly. A single, tubular,outer wall may envelop more than one tubular inner wall equipped withtwo accordeon-like folds in the manner illustrated in FIG. 2, and thesupporting elements transferring the weight of the connecting portion ofeach inner tube to the common outer tube are modified in the mannerdescribed above.

Other modifications and variations of the illustrated embodiment of theinvention will readily suggest themselves to those skilled in the art,and it should be understood that, within the scope and spirit of theappended claims, this invention may be practiced otherwise than asspecifically disclosed.

What is claimed is:

1. A stack for the conveyance of hot gases comprising, in combination:

a. a plurality of sections having each a vertical axis,

1. each section having an outer, upright, axial wall, an inner, upright,axial wall, an upper annular flange, and a lower annular flange, saidflanges connecting said walls transversely to said axis, said walls andflanges jointly bounding a chamber therebetween, and said inner wallbounding a conduit alignedly communicating with respective conduits inother sections,

2. each of said inner walls being formed with two resiliently deformableaccordeon-like folds axially spaced from each other and respectivelyadjacent said upper and lower flanges, said folds permitting thermalexpansion and contraction of said inner wall at a rate different fromthe rate of expansion and contraction of said outer wall, 3. a portionof said inner wall axially connecting said two spaced folds; b.supporting means in each of said plurality of sections for directlytransmitting at least a major portion of the weight of said connectingportion of the inner wall to said outer wall; and

fastening means fixedly fastening respective flanges of adjacentsections to each other.

2. A stack as set forth in claim 1, wherein said supporting meansinclude a first abutment member fixedly fastened to said connectingportion of said inner wall in said chamber, and a second abutment memberfixedly fastened to said outer wall in said chamber and engaging saidfirst abutment member for limiting downward movement of said connectingportion while permitting relative horizontal movement of said connectingportion and of said outer wall.

3. A stack as set forth in claim 2, wherein said abutment members areannular and substantially discshaped in respective planes transverse tosaid axis.

4. A stack as set forth in claim 3, wherein said connecting portion isof substantially uniform cross section from one of said folds to theother fold.

5. A stack as set forth in claim 4, wherein the axial length of saidconnecting portion is greater than one half the total axial height ofsaid section.

UNTTTD STATES TATENT oTTTcE TITLEK'EETiiC/TTE UT QURMQTT'EEON Patent No.3,752,091 Dated August 14, 1973 lnventor(s) EILEEN MO LAWRENCE It iscertified that error appears in the above-identified patent and that'said Letters Patent are hereby corrected as shown below:

In the heading, line i77a Change "Eillen" to Eileen Signed and sealedthis 20th day of November 1973.

(SEAL) Attest:

EDWARD MJLEI'GPIIER,JRa RENE D. TEGTMEYER Attesting Officer ActingCommissioner of Patents DRM Po-wso (10-69) USCOMM-DC 50376-P59 UvS. GOERNMENT PRINTING OFFICE: IBIS O-GGG-SSI.

1. A stack for the conveyance of hot gases comprising, in combination:a. a plurality of sections having each a vertical axis,
 1. each sectionhaving an outer, upright, axial wall, an inner, upright, axial wall, anupper annular flange, and a lower annular flange, said flangesconnecting said walls transversely to said axis, said walls and flangesjointly bounding a chamber therebetween, and said inner wall bounding aconduit alignedly communicating with respective conduits in othersections,
 2. each of said inner walls being formed with two resilientlydeformable accordeon-like folds axially spaced from each other andrespectively adjacent said upper and lower flanges, said foldspermitting thermal expansion and contraction of said inner wall at arate different from the rate of expansion and contraction of said outerwall,
 3. a portion of said inner wall axially connecting said two spacedfolds; b. supporting means in each of said plurality of sections fordirectly transmitting at least a major portion of the weight of saidconnecting portion of the inner wall to said outer wall; and c.fastening means fixedly fastening respective flanges of adjacentsections to each other.
 2. each of said inner walls being formed withtwo resiliently deformable accordeon-like folds axially spaced from eachother and respectively adjacent said upper and lower flanges, said foldspermitting thermal expansion and contraction of said inner wall at arate different from the rate of expansion and contraction of said outerwall,
 2. A stack as set forth in claim 1, wherein said supporting meansinclude a first abutment member fixedly fastened to said connectingportion of said inner wall in said chamber, and a second abutment memberfixedly fastened to said outer wall in said chamber and engaging saidfirst abutment member for limiting downward movement of said connectingportion while permitting relative horizontal movement of said connectingportion and of said outer wall.
 3. A stack as set forth in claim 2,wherein said abutment members are annular and substantially disc-shapedin respective planes transverse to said axis.
 3. a portion of said innerwall axially connecting said two spaced folds; b. supporting means ineach of said plurality of sections for directly transmitting at least amajor portion of the weight of said connecting portion of the inner wallto said outer wall; and c. fastening means fixedly fastening respectiveflanges of adjacent sections to each other.
 4. A stack as set forth inclaim 3, wherein said connecting portion is of substantially uniformcross section from one of said folds to the other fold.
 5. A stack asset forth in claim 4, wherein the axial length of said connectingportion is greater than one half the total axial height of said section.